I certainly found with my Aleph 4 that it would run beautifully cool in the winter with temperatures inside the case at about 45 degrees C. However, in the summer the internals would run at closer to 55 degrees.

The simple solution was to fit a pair of 50mm fans (12V) but running them in series. The result is virtually silent and the temperatures keep the caps well below 50 degrees C.

The fans are above the cap banks with large holes drilled in the base around the caps.